The night of March 3, 2007, is forever seared in the memory of three former college soccer players -- April Grolle, Lauren Chief Elk and Lauren Bryeans.
What they witnessed at a local house party, they said, changed them forever.
It was supposed to be a fun girls night out for the three friends, classmates at De Anza Community College in Cupertino, Calif. They were invited to a party in nearby San Jose by members of their school's baseball team.
"It was a typical baseball party with a lot of alcohol, a lot of people," said Grolle.
But by night's end, it would become anything but typical. The three athletes said they witnessed -- and stopped -- the gang rape of a 17-year-old girl.
Exactly what happened would become a subject of intense controversy. Amid wildly conflicting accounts and citing lack of evidence, the district attorney declined to file criminal charges in the case. A civil suit currently is pending against the ball players, including among other claims allegations of rape and/or failure to stop an assault. The players have insisted any sexual contact was consensual.
Meanwhile Grolle, Chief Elk and Bryeans told "20/20" their story.
Watch the full story on "20/20" Friday at 10 p.m. ET.
The young women met and bonded on the soccer field.
"The three of us have played soccer since we first started walking. ... We became close really fast," said Chief Elk, nicknamed Chief, who was 19 at the time of the alleged attack.
The party was at the home of a star infielder on the De Anza baseball team. When they arrived, the bumping sounds of hip-hop vibrated through the crowd. Liquor was flowing freely, the women said.
During the party, the trio noticed a petite, young blond girl hanging out in the kitchen.
"She had a cute necklace on, so we, you know, complimented her and that was it," said Chief Elk.
Later that night, Grolle noticed the young blond teen again. This time, Grolle said, the teen appeared intoxicated and seemed to be giving a kind of lap dance to one of the baseball players.
"I only watched for a few seconds because it really, to me, wasn't that big of a deal," said Grolle, who was 19 at the time.
Close to midnight, as they were about to leave, something stopped the women in their tracks, they said.
"There was a young girl knocking on these French doors," said Grolle, describing glass doors covered on the inside by a hanging black sheet.
Grolle said the girl knocking on the doors said something that caught the three friends' attention. "There's a girl in there with eight guys," Grolle recalled the girl saying.
"So we took it amongst [sic] ourselves to see what was going on," said Grolle.
When they tried to enter the room, they were confronted by a De Anza player who, they said, was holding the door shut from the inside.
"He said, 'She wants to be in here and she wants this.' And slams the door in our face," said Chief Elk.
Grolle said the baseball player told them, "It's none of our f***ing business.' ... Just the way that he talked to us really got us angry."
After several failed attempts to enter the room, Chief Elk said, she suddenly noticed a small unconcealed area of glass at the bottom of the door. She peered inside. She was stunned, she said, by an unbelievable scene just a few feet away.